Croton sapiifolius Müll.Arg.: a new occurrence for the State of Espírito Santo, Brazil1

(Croton sapiifolius Müll.Arg.: a new occurrence for the State of Espírito Santo, Brazil). While studying Croton material collected in Espírito Santo, we found several specimens of Croton sapiifolius, a species previously restricted to the State of Bahia. The present paper updates our knowledge about the taxonomy, habitat and geographic distribution of C. sapiifolius. This finding increases the number of known Croton species occurring in Espírito Santo State to 20 and contributes to the knowledge of Croton of the Brazilian Atlantic Forest.


Introduction
Croton L., the second largest genus of Euphorbiaceae, comprises about 1.200 species distributed worldwide (Berry et al. 2005). Brazil has 316 species of the genus, which ranks Croton as the 4 th largest Angiosperm genus in the country (BFG 2015). It occurs in almost all types of vegetation, but most species grow in dry and open vegetation, secondary forests and disturbed sites (van Ee et al. 2011, Gomes-Pompa 1971, Caruzo et al. 2011. Croton sapiifolius was described by Müller Argoviensis (1865) as the only species of section Quadrilobus Müll.Arg. Webster (1993) mentioned that the species was poorly known because until then it was only known from the type collection. Riina et al. (2010) updated the description of Croton sapiifolius, designated a lectotype, and recorded new specimens, however, until that moment it was known to occur only in moist forests of southern Bahia.
During studies conducted on the genus Croton at the herbarium of the Universidade Federal do Espírito Santo (VIES; acronym following Thiers 2016), several collections of C. sapiifolius from the State of Espírito Santo were found. According to Dutra et al. (2015), there were 19 species of Croton in the State of Espírito Santo (ES). The present paper documents the first record of Croton sapiifolius for this State, increasing to 20 the number of Croton species known for Espírito Santo and extending the distribution of this species to southeastern Brazil.

Material and methods
This study was based on the analysis of collections deposited in the following herbaria: ALCB, CVRD, MBML, SP, VIES (acronyms according to Thiers 2016).
Morphological characters were observed using a stereomicroscope and the terms used in the description  are following Hickey (1973), Stearn (1992), and Webster et al. (1996).
Croton sapiifolius is endemic to the Atlantic Forest (figure 1), where is found in 'restinga' forests of Espírito Santo State and in moist forests of southern Bahia, from 100 to 200 m elevation (Riina et al. 2010). Flowering from August to October and fruiting in May, October and November. Specimens of Croton sapiifolius from Espírito Santo provide new data and additional morphological variation for the species. For this reason, the current description (Riina et al. 2010) should be complemented with the following features: occurrence of monoecious individuals; presence of stellate-porrect trichomes in other parts of the plant besides the pistillate flowers; presence of reduced petals in the pistillate flowers; styles bifid, with terminal tips sometimes divided once more.
Specimens of Croton sapiifolius were erroneously identified at VIES as C. polyandrus Spreng. Although both species occur sympatrically in 'restinga' forests of the State of Espírito Santo, they can be easily distinguished by their habit (arborescent in C. sapiifolius vs shrubby in C. polyandrus), foliar margin (sinuous or entire in C. sapiifolius vs crenate in C. polyandrus), number of carpels (usually two in C. sapiifolius vs three in C. polyandrus) and inflorescence sexuality (unisexual in C. sapiifolius vs bisexual in C. polyandrus). Another species found in 'restinga' forests of the State of Espírito Santo is Croton sphaerogynus Baill., which differs from Croton sapiifolius in several morphological features (see table 1).
The present paper increases the number of known species of Croton in the State of Espírito Santo to 20 and contributes to the knowledge of Croton species in Brazil.